摘要:
There are provided a sealing composition for a hard disk drive (HDD) motor and a HDD motor fabricated using the same. The sealing composition includes: 45 to 65 parts by weight of urethane methacrylate; 35 to 50 parts by weight of methacrylate; and 2 to 4 parts by weight of acrylic acid. A sealing composition having a new composition is used as a sealing material of a flexible printed circuit (FPC) adhering part of the HDD motor, whereby a haze phenomenon due to air leak and outgas at the FPC adhering part may be improved and reliability of a HDD motor may be enhanced due to a reduction in generation of the outgas of the adhering part.
摘要:
There are provided a hydrodynamic bearing assembly and a method of manufacturing the same. The hydrodynamic bearing assembly includes: a lubricating oil filled so as to form a liquid-vapor interface between stationary members and rotating members; and a lipophilic coating formed on the liquid-vapor interface of the lubricating oil so as to prevent lubricating oil leakage. Therefore, the lipophilic coating is formed on the interface of the lubricating oil and an oil repellent material is formed on a surface of at least one of the stationary members and the rotating members, whereby the scattering and the leakage of the lubricating oil may be effectively prevented.
摘要:
There are provided an adhesive resin composition for a hard disk drive (HDD) motor and a HDD motor fabricated by the using the same. The adhesive resin composition includes: 45 to 55 parts by weight of an urethane methacrylate oligomer, 35 to 45 parts by weight of hydroxylalkyl methacrylate, 1 to 3 parts by weight of an acrylic acid, 1 to 2 parts by weight of organic hydroperoxide, and 2 to 5 parts by weight of a photo initiator. The HDD motor may be fabricated using the adhesive resin composition for a HDD motor prepared by controlling contents of an UV curable adhesive and a primer to reduce generation of outgas, whereby improved reliable quality of the motor may be obtained.
摘要:
There are provided a sealing resin composition for a hard disk drive (HDD) motor and a HDD motor fabricated by using the same. The sealing resin composition includes 40 to 80 parts by weight of epichlorohydrin-4,4-isopropylidene diphenol resin; 5 to 20 parts by weight of acrylated ester; and 5 to 15 parts by weight of acrylated epoxy. The sealing resin composition containing a UV curable epoxy resin is used as a sealing material of the adhering part of the FPC of the HDD motor, whereby generation of outgas in the adhering part may be reduced.
摘要:
Disclosed is a lubricating oil composition which includes a diester-based base oil having an asymmetric structure in which the number of carbons of the alkyl chain bound to one ester group with respect to a central atom is two more than that of the alkyl group bound to the other ester group, and which has low viscosity and a comparatively small amount of evaporation at high temperature. When this composition is used for a motor of a small hard disk, power consumption can be reduced and stability at high temperature can be enhanced.
摘要:
There are provided an adhesive resin composition for a HDD motor and a HDD motor fabricated using the same. The adhesive resin composition for a HDD motor includes: 25 to 35 parts by weight of a bisphenol E-epoxy resin; 10 to 25 parts by weight of an epoxy resin; 10 to 20 parts by weight of mercaptan; and 5 to 15 parts by weight of imidazole. The constituents of an epoxy adhesive material may be controlled, such that a curing speed may be increased, as compared to the case of the related art, thereby enhancing working efficiency and reliability.
摘要:
Disclosed is a lubricating oil composition which includes a diester-based base oil having an asymmetric structure in which the number of carbons of the alkyl chain bound to one ester group with respect to a central atom is two more than that of the alkyl group bound to the other ester group, and which has low viscosity and a comparatively small amount of evaporation at high temperature. When this composition is used for a motor of a small hard disk, power consumption can be reduced and stability at high temperature can be enhanced.
摘要:
A spacer grid for nuclear fuel rods includes a plurality of unit spacer grids stacked one on top of another. Each unit spacer grid includes a plurality of unit spacer grid straps disposed at regular intervals in a row, and a plurality of fixing grid straps connected to respective opposite ends of the unit spacer grid straps so as to fix the unit spacer grid straps. Each unit spacer grid strap has convexities alternating with each other on opposite sides thereof at regular intervals, and at least one of the convexities has a diameter greater than the others. The unit spacer grids are rotated in one direction by a 90 or 180 degree angle when being stacked.
摘要:
Disclosed herein is a guide thimble of a nuclear fuel assembly, which is capable of improving the cooling performance and the stability of a nuclear fuel, preventing a flow split in dual-cooling nuclear fuel rod and guide thimble sub channels for obtaining high combustion degree and high power, and minimizing a neutron absorption section in a reaction degree region. Since the guide thimble having the dual tube type structure is adopted, a flow split in the fuel rod and guide thimble sub channels can be reduced, and the degradation in performance of nuclear fuel due to increase of a neutron absorption section can be prevented. In order for compatibility with an existing control rod, a typical guide tube is used as an inner guide thimble, and an outer guide thimble is provided outside the inner guide thimble. Thus, the guide thimble has the dual tube type structure as a whole, and is coupled to the upper and lower end fittings so that it can prevent a flow unbalance due to the flow split in the fuel rod and guide thimble sub channels.
摘要:
A manufacturing method of a semiconductor device wherein a metal pad is etched to form a trench in which a central part is concave in form, or to form a trench in the shape of a cylinder or a parallelepiped on the edge part of a metal pad. Accordingly, the contact area between a polymide isoindro quirazorindione (PIQ) or similar curable layer and the metal pad is increased and the bondability is improved. Accordingly, the technology of improving the characteristic of device by preventing the problem that the metal pad is excessively opened in a subsequent curing process and the layer of a lower portion of the metal pad is attacked is disclosed.